The field of the invention relates generally to turbine engines, and more particularly, to fuel distribution systems within turbine engines.
At least some known turbine engines include a forward fan, a core engine, and a power turbine. The core engine includes at least one compressor that provides pressurized air to a combustor where the air is mixed with fuel and ignited for use in generating hot combustion gases. Generated combustion gases flow downstream to one or more turbines that extract energy from the gas to power the compressor and provide useful work, such as powering an aircraft. A turbine section may include a stationary turbine nozzle positioned at the outlet of the combustor for channeling combustion gases into a turbine rotor downstream thereof. At least some known turbine rotors include a plurality of circumferentially-spaced turbine blades that extend radially outward from a rotor disk that rotates about a centerline axis of the engine.
In at least some known combustors, fuel and air are injected into an oxidizer stream from respective pluralities of circumferentially-spaced outlets. The independent streams of fuel and air interact to form a mixture, which produces a lean combustion flame that reduces NOx emissions. However, in some known systems, the fuel outlets are axially spaced from the air outlets and the outlets for the fuel and the air are circumferentially spaced. As such, the resulting fuel and air mixture is not uniformly mixed in the radial and circumferential directions. Also, in some known systems, the fuel injectors require a relatively high pressure drop across the fuel outlets to meet fuel-air mixing and emissions goals under maximum power operating conditions. As such, the fuel pump requires a high amount of power to provide the fuel with enough momentum to facilitate satisfactory mixing.